Analysis On Performance Of BitTorrent Content Distribution Based On LT Codes

After Shannon channel coding theory being presented, some scholars show a series of designed good codes and effective decoding methods. Through 60-year development, error correction codes have been developed a lot in theory and practice. Based on FEC technique, for the past ten years, scholars committed to this area have presented various erasure codes which are used to re-propagate message data and realize real-time reliable propagation.This thesis mainly analyzes encoding and decoding algorithms of LT codes after grasping the theory of erasure codes, and focuses on the application of LT codes in BitTorrent Content Distribution System. Some results are obtained and summarized as follow:1. The basic principle of erasure codes is illuminated. The encoding, decoding and construction methods and performance of LT codes are studied.2. The P2P technology is briefly summarized. BitTorrent Content Distribution System and its working principle, main protocols and algorithms are analyzed.3. According to a solution to "BitTorrent Content Distribution System on the basis of LT codes"(LTBT), the design and realization of all the modules of LTBT system client are illustrated.4. The encoding module Unit and decoding performance of LTBT System are tested. After analysis on the performance of "LTBT", the superiorities of LT codes' application in BitTorrent System are showed.